The present invention relates to rocker spring units which provide controlled rocking capability to chairs in which they are used. More particularly, the present invention relates to rocker spring units of the foregoing sort which are also adaptable for use with a swivel means to provide the rocker chairs in which they are used with controlled swiveling capability.
A functional rocker spring unit of the type described herein is disclosed in U.S. Pat. No. 3,190,693. The swivel rocker unit of this patent utilizes a base member which is arranged for swivel mounting on a swivel means and which has upwardly extending opposite side portions that are flanged outwardly along their upper edges to present elongated rocker supporting areas. Also included is a bracket component of complementary form in that it has corresponding downwardly extending opposite side portions that are flanged outwardly at the lower edges to present curved rocker surfaces which engage and ride upon the base member support areas. The rocker springs are attached to the inside of the base member's upwardly extending side portions and also to the upper face of the bracket component. Apertured outwardly extending tab sections cut from the side portion of the bracket component are provided for chair frame attachment.
The rocker spring unit of this prior patent offers significant advantages, but it is rather difficult to assemble because of the internal disposition of the rocker springs. Also, the chair frame attachment tabs, being cut from the side portions of the bracket component, are difficult to strengthen adequately, and difficulty has been encountered in maintaining the rocker surfaces in riding position consistently during use of the unit because of the necessarily narrow width of the rocker surfaces and support areas.
Such difficulties are eliminated, and a rocker spring unit of much simplified construction is provided, by the present invention.